An electrical testing machine includes a base having two parallel first rails, a platform provided on the base, a probe holder provided on the base and having a plurality of placement locations, a support provided between the first rails and having a second rail thereon, a test arm provided on the second rail and above the platform, a receiving seat provided on the test arm, and a plurality of probe sets, wherein one of the probe sets is engaged on the receiving seat, while the others are respectively provided on the placement locations. The support is movable relative to the base and the platform. The test arm is movable along with the support, and is also movable relative to the support. The receiving seat is movable or rotatable relative to the test arm. The probe set engaged on the receiving seat is movable along with the receiving seat.